I have a 99 ZL500 with carb's and I only get 7.9 MPG... The sled just got the top end rebuilt and carb's cleaned and adj. The sled runs great all the time. But I don't understand why it get's such poor gas mileage. Before it got rebuild it also got bad gas mileage. It's also got 360 main jets in it. Any suggestions would be greatly appreciated!